Work chuck



Sept. 26, 1944. t G. FLZOTO 2,358,918,

WORK CHUCK Filed Aug. 2, 1943 2 Sheets-She et 1 Patented Sept. 26, 1944 UNITED STATES PATENT OFFICE 2,358,918 WORK CHUCK 1 Louis G. Floto, Steubenville, Ohio Application August 2, 1943, Serial No. 497,975 1 Claim. (or. 279-2) This invention relates to work chucks for lathes, and the like.

The primary object of the invention is to provide an improved chuck of the above kind, which is adapted to effectively hold and center tubular work, and which is positive and accurate in action.

With the above general object in view, and others that will appear when the nature of the invention is better understood, the present in-' vention consists in the novel form, combination and arrangement of parts hereinafter more fully described, shown in the accompanying drawings, and claimed.

In the drawings:

Figure l is a side elevation view showing a chuck embodying the present invention.

Figure 2 is a vertical transverse section on line 2-2 of Figure 1.

Figure 3 is an elevation looking toward the left of Figure 1.

Figure 4 is a section on line 4-4 of Figure 3; and

Figure 5 is a perspective view of the frustoconical jaw-expanding member of the chuck shown in Figures 1 to 4 inclusive.

Referring in detail to the drawings, the present chuck includes a disk 5 having a hub Bthreaded onto the forward end of a tubular spindle or shaft 1, journaled in spaced bearings 8, and 8a of a lathe or the like, and adapted to be driven at various speeds by a driving belt selectively engageable with a desired one of three pulleys of different sizes secured on the spindle or shaft 1 between the bearings 8 and 8a, as at 9, 9a, and

The disk 5 has four equally spaced radially arranged elongated slots 10, in each of which is slidably fitted a rearwardly projecting lug ll of a segmental work engaging jaw l2 having a plurality of arcuate stepped work-engaging surfaces [3, Ba, 13b, and 130. There are preferably four similar jaws l2 which co-operate to provide a plurality of substantially cylindrical surfaces to receive tubular work of various internal diameters. 'The inner faces of jaws l2 are arcuate and tapered larger forwardly as at M, and engaging the peripheryof a frusto-conical jaw-expanding member 15 secured on the forward end of a rod l6 slidably extending through shaft 1. Thus, upon pulling the rod l6 rearwardly, the jaws l2 may be radially expanded to increase the range of work capable of being held thereby and to tightly engage the inner surface of any piece of tubular work slipped onto any of the surfaces [3, I311, B1) or l3c of the jaws H.

For drawing the member l5 rearwardly to expand the jaws, a nut member l1 having an operating wheel 18 and handle ,I 9, is threaded on the rear end of rod I6 and has an antifriction bearat the outer sides ing interposed between it and the bearing 8, as at 20.

A spring 2! is interposed between the member 15 and the forward end of shaft 1 to urge the member l5 forwardly and permit contraction of jaws l2 when the rod I6 is allowed to move forwardly by turning nut l1 inone direction. Ob-, viously, nut I1 is turned in the opposite direction to draw the rod l6 and member l5 rearwardly against the action of spring 2|, in order to expand jaws l2.

Springs 22 are radially arranged between the outer walls of slots l0 and the lugs H to contract the jaws 12 when the member 15 is moved for wardly. These springs are engaged at their ends over studs 23, on lugs H and the inner ends of screws 24 threaded through the outer end walls of slots ID. Plates 2'5 are secured by screws 26 or the like, on the rear or inner ends of lugs II and overlap the rear face of disk 5 at opposite sides of slots ID, to secure the jaws l2 in assembled relation to said disk 5. 7

From the foregoing description, it is believed that the construction and operation, as well as the advantages of the present invention, will be readily understood and appreciated by those skilled in the art. The device is simple, durable, and efficient, and offers an internal chuck, for tubular work, which is easy to operate and use.

What I claim is: v

A work chuck of the character described, comprising a tubular shaft, a disk secured on one end of said shaft, and having a plurality of equally spaced radial elongated slots, a plurality of segmental jaws each having a plurality of arcuate stepped work engaging surfacesand a rearwardly projecting lug slidably fitted in one of said slots, compression'springs acting upon said lugs of the latter to normally yieldingly urge-said jaws radially inwardly to contracted position, said jaws further having arcuate inner faces tapered larger forwardly, a frustoconical expanding member engaging said inner surfaces of the jaws and movable rearwardly to expand the jaws, a rod slidable through said tu bular shaft and carrying said expanding member, means to move said rod to expand said jaw, and a spring interposed between said tubular shaft and said expanding member to urge thelatter forwardly and permit contraction of said jaws, studs 'on the outer sides of said lugs, screws threaded through the outer walls of said slots, each of said compression springs having its ends respectively engaged over one of said studs and one of said screws, and plates secured on the inner ends of said lugs and overlapping the rear face of said disk at opposite sides of said slots.

Louis a. more. 

